I was unable to do this problem by changing Win11 registry entry
HKEY_CURRENT_USER\Software\Obviously Nice\x2goclient\settings\useintx
(use internal X) from false back to true.

I did not have xcXsrv installed which is why it couldn’t find an X11 program.

A fix would be not to fall x2goclient over but to allow one to amend Settings/X.Org Server settings

I will explore more as to implement fix the repeating keys probels